Aquatic modules for bioregenerative life support systems based on the C.E.B.A.S. biotechnology [correction of biotechnilogy]

Development of top-dressing automation technology for sustainable shrimp aquaculture in India

Globally, the shrimp farming industry faces increasing challenges and pressure to reduce the broken shrimps and maintain a healthier pond environment. Shrimps lack an adaptive immune system to combat invading pathogens due to an imbalance in beneficial gut microbiota. The use of top-dressing agents like probiotics and pond optimizes is an alternative strategy to improve the innate immune system leading produce disease-free shrimp in international markets. The cost of top-dressing agents is accounted for 20% of the production cost and therefore, the development of top-dressing automation technology is important to maintain and improve the financial and environmental viability of shrimp sustainable farming. This perspective described several sensor-based aquaculture technologies for on-farm management systems but sustainability in the aquaculture industry is not yet achieved in practice. The present technology is a new invention to reduce labor and production costs required for reducing bacterial and organic loads in Biofloc shrimp cultures. Aquaculture automation system disperses the top-dressing agents to the shrimp ponds based on the signals received from microbial and environmental sensors. Continuous monitoring of shrimp growth, mortality, immune responses, diseases, and pond water quality parameters will fetch larger profits with additional savings on labor and production costs for sustainable shrimp aquaculture in India.

Symbiotic integration of bioprocesses to design a self-sustainable life supporting ecosystem in a circular economy framework

Climate change, resource depletion and unsustainable crop productivity are major challenges that mankind is currently facing. Natural ecosystems of earth's biosphere are becoming vulnerable and there is a need to design Bioregenerative Life Support Systems (BLSS) which are ecologically engineered microcosms that could effectively deal with problems associated with urbanization and industrialization in a sustainable manner. The principles of BLSS could be integrated with waste fed biorefineries and solar energy to create a self-sustainable bioregenerative ecosystem (SSBE). Such engineered ecosystems will have potential to fulfil urban life essentials and climate change mitigation thus generating ecologically smart and resilient communities which can strengthen the global economy. This article provides a detailed overview on SSBE framework and its improvement in the contemporary era to achieve circular bioeconomy by means of effective resource recycling.

On the Way to Mars-Flagellated Algae in Bioregenerative Life Support Systems Under Microgravity Conditions

For long-term manned interplanetary missions it is not feasible to carry the necessary oxygen, food, and water to sustain the astronauts. In addition, the CO2 exhaled by the astronauts has to be removed from the cabin air. One alternative is to utilize photosynthetic organisms to uptake the CO2 and produce oxygen. In addition to higher plants, algae are perfect candidates for this purpose. They also serve to absorb wastes and clean the water. Cyanobacteria can be utilized as food supplement. Early ground-based systems include micro-ecological life support system alternative, closed equilibrated biological aquatic system, and the Biomass Production Chamber. The AQUARACK used the unicellular flagellate Euglena which produced the oxygen for fish in a connected compartment. A number of bioregenerative systems (AQUACELLS, OMEGAHAB) have been built for experiments on satellites. A later experiment was based on a 60-ml closed aquatic ecosystem launched on the Shenzhou 8 spacecraft containing several algae and a small snail living in adjacent chambers. Recently the Eu : CROPIS mission has been launched in a small satellite within a Deutschen Zentrum für Luft- und Raumfahrt (DLR) program. In addition to tomato plants, Euglena is included as oxygen producer. One new approach is to recycle urine on a bacterial filter to produce nitrogen fertilizer to grow vegetables.

Microgravity effects on different stages of higher plant life cycle and completion of the seed-to-seed cycle

Human inhabitation of Space requires the efficient realisation of crop cultivation in bioregenerative life-support systems (BLSS). It is well known that plants can grow under Space conditions; however, perturbations of many biological phenomena have been highlighted due to the effect of altered gravity and its possible interactions with other factors. The mechanisms priming plant responses to Space factors, as well as the consequences of such alterations on crop productivity, have not been completely elucidated. These perturbations can occur at different stages of plant life and are potentially responsible for failure of the completion of the seed-to-seed cycle. After brief consideration of the main constraints found in the most recent experiments aiming to produce seeds in Space, we focus on two developmental phases in which the plant life cycle can be interrupted more easily than in others also on Earth. The first regards seedling development and establishment; we discuss reasons for slow development at the seedling stage that often occurs under microgravity conditions and can reduce successful establishment. The second stage comprises gametogenesis and pollination; we focus on male gamete formation, also identifying potential constraints to subsequent fertilisation. We finally highlight how similar alterations at cytological level can not only be common to different processes occurring at different life stages, but can be primed by different stress factors; such alterations can be interpreted within the model of 'stress-induced morphogenic response' (SIMR). We conclude by suggesting that a systematic analysis of all growth and reproductive phases during the plant life cycle is needed to optimise resource use in plant-based BLSS.

Lunar astrobiology: a review and suggested laboratory equipment

In October of 2005, the European Space Agency (ESA) and Alcatel Alenia Spazio released a "call to academia for innovative concepts and technologies for lunar exploration." In recent years, interest in lunar exploration has increased in numerous space programs around the globe, and the purpose of our study, in response to the ESA call, was to draw on the expertise of researchers and university students to examine science questions and technologies that could support human astrobiology activity on the Moon. In this mini review, we discuss astrobiology science questions of importance for a human presence on the surface of the Moon and we provide a summary of key instrumentation requirements to support a lunar astrobiology laboratory.

Culture of Spirulina platensis in human urine for biomass production and O(2) evolution

Attempts were made to culture Spirulina platensis in human urine directly to achieve biomass production and O(2) evolution, for potential application to nutrient regeneration and air revitalization in life support system. The culture results showed that Spirulina platensis grows successfully in diluted human urine, and yields maximal biomass at urine dilution ratios of 140 approximately 240. Accumulation of lipid and decreasing of protein occurred due to N deficiency. O(2) release rate of Spirulina platensis in diluted human urine was higher than that in Zarrouk medium.

Real-time studies on microalgae under microgravity

Using remote sensing technique, we investigated real-time Nostoc sphaeroides Kütz (Cyanobacterium) in Closed System under microgravity by SHENZHOU-2 spacecraft in January 2001. The experiments had 1 g centrifuges in space for control and ground control group experiments were also carried out in the same equipments and under the same controlled condition. The data about the population growth of Nostoc sp. of experiments and temperature changes of system were got from spacecraft every minute. From the data, we can find that population growth of Nostoc sp. in microgravity group was higher than that of other groups in space or on ground, even though both the control 1 g group in space and 1 g group on ground indicated same increasing characteristics in experiments. The growth rate of 1.4 g group (centrifuged group on ground) was also promoted during experiment. The temperature changes of systems are also affected by gravity and light. Some aspects about those differences were discussed. From the discussion of these results during experiment, it can be found that gravity is the major factor to lead to these changes.

Performance of a simple Closed Aquatic Ecosystem (CAES) in space

A simple Closed Aquatic Ecosystem (CAES) consisting of single-celled green algae (Chlorella pyrenoidosa, producer), a spiral snail (Bulinus australianus, consumer) and a data acquisition and control unit was flown on the Chinese Spacecraft SHENZHOU-II in January 2001 for 7 days. In order to study the effect of microgravity on the operation of CAES, a 1 g centrifuge reference group in space, a ground 1 g reference group and a ground 1 g centrifuge reference group (1.4 g group) were run concurrently. Real-time data about algae biomass (calculated from transmission light intensity), temperature, light and centrifugation of the CAES were logged at minute intervals. It was found that algae biomass of both the microgravity group and the ground 1 g-centrifuge reference group (1.4 g) fluctuated during the experiment, but the algae biomass of the 1 g centrifuge reference group in space and the ground 1 g reference group increased during the experiment. The results may be attributable to influences of microgravity and 1.4 g gravity on the algae and snails metabolisms. Microgravity is the main factor to affect the operation of CAES in space and the contribution of microgravity to the effect was also estimated. These data may be valuable for the establishment of a complex CELSS in the future.

The development of gravity sensory systems during periods of altered gravity dependent sensory input

Gravity related behavior and the underlying neuronal networks are the most suitable model systems to study basic effects of altered gravitational input on the development of neuronal systems. A feature of sensory and motor systems is their susceptibility to modifications of their adequate physical and/or chemical stimuli during development. This discovery led to the formulation about critical periods, which defines the period of susceptibility during post-embryonal development. Critical periods can be determined by long-lasting modifications of the stimulus input for the gravity sensory system (GSS). Techniques include: (1) destruction of the gravity sense organ so that the gravity cannot be detected any longer and the central neuronal network of the GSS is deprived of gravity related information, (2) loading or deloading of parts of the body by weights or counterweights, respectively, which compensates for the gravitational pull, and (3) absence or augmentation of the gravitational environment per se by the exposure of organisms to microgravity during spaceflights or to hypergravity by centrifugation. Most data came from studies on compensatory eye or head movements in the clawed toad Xenopus laevis, the cichlid fish Oreochromis mossambicus, and crickets (Acheta domesticus, Gryllus bimaculatus). The responses are induced by a roll or pitch stimulation of the gravity sense organs, but are also affected by sensory inputs from proprioreceptors and eyes. The development of these compensatory eye and head responses reveals species-specific time courses. Based on experiments using spaceflights, centrifugation, lesion and loading or deloading, all species revealed a significant susceptibility to modifications of the gravity sensory input during development. Behavioral responses were depressed (Xenopus) or augmented (Xenopus, Oreochronis) by microgravity, and depressed by hypergravity except in crickets. In Acheta, however, the sensitivity of its position sensitive neuron PSI was reduced by microgravity. After termination of the period of modified gravity sensory input, all behavioral and physiological modifications disappeared, in some preparations such as the PSI of Acheta or the eye response in Xenopus, however, delayed after exposure to hypergravity. Irreversible modifications were rare; one example were malformations of the body of Xenopus tadpoles caused by lesion induced deprivation. Several periods of life such as the period of hatching or first appearance of gravity related reflexes revealed a specific sensitivity to altered gravity. Although all studies gave clear evidences for a basic sensitivity of developing GSSs to long-lasting modifications of the gravity sensory input, clear arguments for the existence of a critical period in the development of the sense of gravity are still missing. It has to take into consideration that during long-term exposures, adaptation processes take place which are guided by central physiological and genetically determined set points. The International Space Station (ISS) is the necessary platform of excellence if biological research is focussed on the analysis of long-term space effects on organisms.